Assessment of Germination of Agrostis Cultivars in Vitro at Optimal and Low Temperatures.

Creeping bentgrass (Agrostis stolonifera L.) is commonly used for early spring establishment on golf course putting greens in the northern United States. However, little information is available on the influence of low temperatures on germination of various bentgrass cultivars. Two laboratory studies were conducted to assess timing and total germination of 74 cultivars of bentgrass at low and optimal temperatures. For each study, 100 seeds of each cultivar were placed on a square dimpled blotter paper moistened with 5 ml de-ionized water and placed in a petri dish. Plates were incubated at either 10C in complete darkness for the low temperature treatment or 25/15C on an 8/16 hour light/dark cycle for the optimal germination. Germinated seeds were counted every 1 to 3 days for 28 days for the 10C treatment and on the 7^th and 28^th day of incubation for the optimal treatment. Studies were arranged as a completely randomized design with three replications and repeated twice. All data were analyzed using the MIXED procedure in SAS. An interaction between replications of each experiment existed so each was analyzed separately. For the optimal germination study, 50 and 33 cultivars had similar germination (>92%) after 28 days of incubation for experiment one and two, respectively. Across both experiments of Study I, the least amount of germination averaged 20%. At 10C, ‘Pure Select’ had the greatest germination with 69 to 77% germination across both experiments. Lowest germination ranged from 0.3 to 9.3% among 13 and 23 cultivars for experiment one and two, respectively. Results indicate that germination of bentgrass cultivars may vary by a variety of factors, including temperature.